Apparatus and method of producing a sensing substrate

ABSTRACT

An occupant or object sensing system in a vehicle includes electrical circuits for resistive and/or capacitive sensing and corresponding circuits shielding the sensing system from interference. A sensing circuit and a shielding circuit may be printed by screen printing with conductive ink on opposite sides of a non-conductive substrate. The substrate is a plastic film or other fabric that has an elastic memory structure that is resilient to stretching. The conductive inks used to print circuits onto the substrate have a similar resilience to stretching such that the substrate and the circuits thereon can be subject to deforming forces without breaking the printed circuits. The substrate may be covered with a carbon polymer layer to provide alternative conductive paths that enable fast recovery for conduction in the presence of any break in the printed conductive traces on the substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and incorporates by reference U.S.Provisional Patent Application Ser. No. 62/953,294 filed on Dec. 24,2019, and entitled Apparatus and Method of Producing a SensingSubstrate.

BACKGROUND

Current implementations of capacitive sensing and resistive sensingtechnologies are often configured for placing on, within, or aroundautomobile components, such as steering wheels and the like, or possiblywithin a vehicle seat. For example, conductive objects, like a humanbody, can induce electrical responses, either resistive or reactive, inthe sensing systems that are useful for occupant detection. An occupantdetection system may comprise one or both of a seat weight sensor thatcan use resistance measurements to calculate weight affecting the sensorand an electric field sensor that can calculate presence, position, andcertain identifying features of an occupant or an occupant's location inthe vehicle. Each of these sensors is operatively connected to acontroller for monitoring vehicle occupancy.

In earlier known embodiments, the seat weight sensor has been adapted togenerate a measure of weight upon the vehicle seat, e.g., upon theassociated seat bottom. Similarly, the electric field sensor may includeat least one electrode located, for example, in the seat bottom underthe seat cover and close to the top of a foam cushion. The electricfield sensor is adapted to enable detection and classification of a typeof occupant or object that may be upon the seat bottom of the vehicleseat.

Traditional capacitive sensors and their associated shielding systemsare often layered assemblies that include a sensor mat, a shieldinglayer, and/or a heating mat that collectively allow for physicaldetection of an occupant's body, an occupant's position in a vehicle, orplacement of an object in a vehicle. Generally, in prior embodiments, apower source provides a voltage signal to a shield mat to provideelectrical shielding for a sensor mat. Interference with the electricalsignal(s) carried by the sensor mat may occur due to the proximity ofthe sensor mat to a metal object such as a steering wheel or seat frame,and providing the shielding voltage signal to the shield mat reduces orprevents this interference with desirable electric field measurements.In addition, the system may also include a heater mat. The heater matmay be separate from the shield mat or it may be used as a combinationheater and shielding mat. To use the heater mat as a shield mat, thepower source generates a heating current for heating or the shieldingvoltage signal for using the heater mat as a shield mat. The heatingcurrent is typically greater than a shielding current.

As used herein, the term “electric field sensor” refers to a sensor thatgenerates a signal responsive to the influence of that being sensed uponan electric field. Generally, an electric field sensor comprises atleast one electrode to which is applied at least one applied signal andat least one electrode—which could be the same electrode or electrodesto which the applied signal is applied—at which a received signal (e.g.,capacitive response or change in resistance) is measured. In operation,the applied signal generates an electric field from the at least oneelectrode to a ground in the environment of the at least one electrode,or to another at least one electrode. The applied and received signalscan be associated with the same electrode or electrodes, or withdifferent electrodes. The particular electric field associated with agiven electrode or set of electrodes is dependent upon the nature andgeometry of the electrode or set of electrodes and upon the nature ofthe surroundings thereto, for example, the dielectric properties of thesurroundings. For a fixed electrode geometry, the received signal orsignals of an electric field sensor are responsive to the applied signalor signals and to the nature of the environment influencing theresulting electric field, for example to the presence and location of anobject having a permittivity or conductivity different from that of itssurroundings.

One form of electric field sensor is a capacitive sensor, wherein thecapacitance of one or more electrodes is measured—from the relationshipbetween received and applied signals—for a given electrodeconfiguration. What has commonly been referred to as capacitive sensingactually comprises the distinct mechanisms of what those in the artrefer to as “loading mode,” “shunt mode”, and “transmit mode” whichcorrespond to various possible electric current pathways. In the “shuntmode”, a voltage oscillating at low frequency is applied to a transmitelectrode, and the displacement current induced at a receive electrodeis measured with a current amplifier, whereby the displacement currentmay be modified by the body being sensed. In the “loading mode”, theobject to be sensed modifies the capacitance of a transmit electroderelative to ground. In the “transmit mode”, the transmit electrode isput into circuit transmission with the user's body, which then becomes atransmitter relative to a receiver, either by direct electricalconnection or via capacitive coupling.

Accordingly, the electric field sensor is either what is commonly knownas a capacitive sensor, or more generally an electric field sensoroperating in any of the above described modes. The electric field sensorcomprises at least one electrode operatively coupled to at least oneapplied signal so as to generate an electric field proximate to the atleast one electrode, responsive to the applied signal. The appliedsignal, for example, comprises either an oscillating or pulsed signal.At least one electrode is operatively coupled to a sensing circuit thatoutputs at least one response signal responsive to the electric field atthe corresponding electrode wherein the response signal is responsive toat least one electric-field-influencing property—for example, dielectricconstant, conductivity, size, mass or distance—of an object proximate tothe electric field sensor. For example, for the electric field sensoroperating as a capacitance sensor, the sensing circuit measures thecapacitance of at least one electrode with respect to either anotherelectrode or with respect to a surrounding ground, for example, a seatframe of the vehicle seat, connected to circuit ground. The at least oneapplied signal is, for example, generated by the sensing circuit thatalso outputs the at least one response signal. The sensing circuit andassociated applied signal may be adapted to be responsive to theinfluence of a water-soaked vehicle seat, on measurements from theelectric field sensor.

Stated in another way, the electric field sensor has a relatively shortrange and principally senses an occupant when a large surface of theoccupant is relatively close to the sensor. Occupants normally seateddirectly on the seat cover typically have a large surface of their bodyrelatively close to the electrode. When infants or children are in childseats, most of their body is elevated several inches off the seat bottomsurface, resulting in a relatively small influence upon the electricfield sensor. The electric field sensor in the seat bottom distinguishesbetween types of occupants in a seat. For example, a large bodyimmediately above the seat cover—for example a normally seated, forwardfacing adult occupant in the seat induces a capacitive response that isdistinguishable from an infant or child seat, including rear facing,front facing and booster seats that are often located on a vehicle seat.In at least one prior art embodiment, when the vehicle seat contains achild seat (including a rear facing infant seat, a forward facing childseat and a booster seat), or when the vehicle seat is empty, no forwardfacing occupant is detected near to the seat bottom and, as a result,the electric field sensor may be connected to other vehicle systemscausing a restraint actuator, such as an ignitor in a vehicle air bag,to be disabled.

The above described technology has also been incorporated in occupantclassification systems using a single circuit as both a heater and asensor. The seat may include a heater controller to regulate the heatersin the seat bottom and/or the seat back and an electronic control unit(ECU) coupled to the sensors in the seat bottom and/or seat back areconfigured to detect and categorize an object or occupant in the seat.The ECU may include sensing and measurement circuits. If the sensor isintegrated into the heater system, the heater controller and the ECU maybe connected in series such that power and/or control signals may beprovided to the conductor (i.e., sensing and heater device) by, forexample, the heater controller through the ECU. While the heatercontroller and the ECU are often provided under the seat bottom of avehicle, in various embodiments the heater controller may be providedelsewhere in the vehicle.

Up to now, the Occupant Classification Systems of the prior art havedepended upon either the above noted capacitive sensing methods or aseat weight rail system. A seat weight rail system measures deflectionof the seat rails and determines a weight on the seat. This gives 5states of measurement: 1yo, 3yo, 6yo, 5th female, 50th male. This systemis expensive and heavy (a concern for electric vehicles).

Embodiments of an Occupant Classification System using seat weight railsystems, capacitive sensing, and heater as a sensor embodiments havebeen heavily scrutinized by regulatory bodies in the United States andabroad. For example, in the United States, Federal Motor Vehicle SafetyStandards No. 208 (FMVSS 208) has recognized deficiencies in the use ofcapacitive sensing and heater as a sensor embodiments for occupantclassification. In particular, these prior embodiments do not adequatelyprovide clear occupant classification distinctions between vehicleoccupants that, with the technology described above, must be groupedtogether. For example, in the case of capacitive sensing, the system isnot accurate enough to provide classification beyond “large” (e.g., 5thpercentile sized female and larger) and “small” (infant or empty vehicleseat). A system of occupant classification, using capacitive sensing,for example, may distinguish a general division in classes withinfant—female separation in weight classes providing the onlyclassification threshold. This threshold, however, does not provide thebest resolution to distinguish the characteristics of occupants withinthe large and small categories.

Infant-Female separation is a weight-based measurement system usingcapacitance as described above but only provides a two-state solution.Several publicly available charts promulgated by the National HighwayTraffic Safety Administration show how the United States regulationFMVSS 208 has mapped certain unidentifiable and non-classifiable greyzones in traditional occupant classification systems, namely a systemusing a heater as a sensor technology for capacitive sensing. The greyzones in these public documents reflect that currently used occupantsystems are largely ineffective to determine physical characteristics,and associated safety protocols, when occupants are between thetraditional small and large classifications (e.g., small adults sizedlarger than a six-year old child and smaller than a 5^(th) percentilefemale, as well as adults sized between 5^(th) percentile females and50^(th) percentile males).

In other embodiments of relevant technology, the seat weight sensor isresponsive to a force upon the vehicle seat. The seat weight sensor, forexample, may comprise one or more load cells operatively coupled to atleast one load path between the seat bottom and the vehicle, e.g.between the seat frame and the floor pan of the vehicle, e.g. at thecorners of the seat frame, so as to measure the weight of the entirevehicle seat and objects or occupants placed thereon. For example, theone or more load cells could use a strain gauge, a magnetic-restrictivesensing element, a force sensitive resistive element, or another type ofsensing element to measure the associated load. For example, the seatweight sensor may be constructed in accordance with the teachings ofU.S. Pat. Nos. 5,905,210, 6,069,325 or 6,323,444, each of which isincorporated herein by reference.

The seat weight sensor may alternately comprise at least one masssensing element, e.g. a force sensitive resistive element, a membraneswitch element, a pressure sensitive resistive contact, a pressurepattern sensor, a strain gauge, a bend sensor, or a hydrostatic weightsensing element, operatively coupled to one or more seating surfaces inthe seat base or seat back, e.g. in accordance with the teachings ofU.S. Pat. Nos. 5,918,696, 5,927,427, 5,957,491, 5,979,585, 5,984,349,5,986,221, 6,021,863, 6,045,155, 6,076,853, 6,109,117 or 6,056,079, eachof which is incorporated herein by reference. Currently there arehundreds of patents with regards to measuring the weight of a seat witha seated occupant. The patents also include or reference using theoutput of said sensor to classify an occupant as a child, 5th female ,or 50th male for the purpose of tailoring actions or reactions of anautomotive safety system. A small sample of the state of the art includepatents and patent applications originating with the applicant assigneeof this disclosure, such as but not limited to U.S. patent applicationSer. No. 16/442,209; U.S. Patent Pub. No. 2018/0022233, US6342683B1,DE69929104T2, JPH11304579A, JP2000258232A, JP2002267524A, JP2001150997A,JPH11351952A, JP2000180255A, JP2004205410A, JP2003177052A,JP2001041813A, JP2006003146A, JP2000258234A, EP0990565A1, JP2005037357A,JP2005037358A, JP2005037356A, JP2001108513A, CN1702439A, JP2005024289A,US6571647B1, US20040262956A1, US6617531B1. All of the patents and patentpublications referenced herein are incorporated by reference as if setforth in their entirety herein.

Problems arise in the above described technologies, however, whenlayered assemblies are too thick or bulky for installing in conjunctionwith various components of a vehicle, or the materials used in thelayers are not amenable to forming into a desirable shape for a givenapplication. Accordingly, there is a need in the art for improvedsystems and methods for making resistive sensor systems and capacitivesensor systems such that the sensors can be placed in more diverse areasof a vehicle body. Of course, all improvements to the structures of acapacitive sensing system must still reliably provide changes inelectrical outputs that can be used for numerous occupant detection andoccupant safety purposes.

BRIEF SUMMARY

A seat assembly for a vehicle includes a deformable seat surfaceconnected to a seat frame and a flexible substrate connected to thedeformable seat surface. At least one conductive ink trace is positionedon the flexible substrate, and the conductive ink trace is configured tobend in response to a deforming load applied to at least a portion ofthe conductive ink trace. The conductive ink trace has an electricalresistance that fluctuates according to a degree of deformation of theconductive ink trace in response to the bend.

One non-limiting implementation of capacitive sensing technologiesaccording to this disclosure is a sensor system that includes a sensorcircuit construction configured for placement in or on multiplestructures within the interior of a vehicle. A circuit construction mayinclude a base substrate, layer or sheet that allows for constructing aresistive sensor circuit and a capacitive sensor circuit on a first sideof the substrate. A second side of the substrate supports a shieldcircuit thereon such that the sensing and shielding operations of theoverall sensor system include a minimal number of layers to install. Infact, by utilizing printing operations and conductive ink products, bothof the sensor circuits and the shield circuit can be formed on oppositesides of a single layer (i.e., a single substrate).

In one non-limiting embodiment, a sensor for occupant monitoring in avehicle includes a flexible substrate that is resilient to a deformingload thereon. A plurality of conductive traces are on the flexiblesubstrate, and the conductive traces are configured for bending inresponse to the deforming load applied to the flexible substrate and theconductive traces. A resistive sensor circuit is on a first side of theflexible substrate, and the resistive sensor circuit includes arespective set of the conductive traces, wherein the resistive sensorcircuit has an electrical resistance that fluctuates according to adegree of deformation of the respective set of the conductive traces inresponse to the bending.

In another embodiment, a seat assembly for a vehicle includes adeformable seat surface connected to a seat frame. A flexible substrateis positioned in proximity to the deformable seat surface in a positionthat a deforming load on the deformable seat surface transfers to theflexible substrate. At least one conductive ink trace is on the flexiblesubstrate, and the at least one conductive ink trace is configured tobend in response to the deforming load applied to at least a portion ofthe at least one conductive ink trace. At least one conductive ink tracehas an electrical resistance that fluctuates according to a degree ofdeformation of the at least one conductive ink trace in response to thebend.

A system of occupant detection in a seat assembly of a vehicle includesa deformable seat surface connected to a seat frame. A flexiblesubstrate is positioned to receive a deforming load from the deformableseat surface. At least one conductive ink trace is on the flexiblesubstrate, and the conductive ink trace is configured to bend inresponse to a deforming load applied to at least a portion of theconductive ink trace. The conductive ink trace has an electricalresistance that fluctuates according to a degree of deformation of theconductive ink trace in response to the bend. A voltage source inelectrical communication with a first end of said conductive ink trace.A computer having a processor and memory in data communication with theopposite end of the conductive ink trace, wherein the computer measuresa change in resistance of the conductive ink trace due to the bend, andthe computer is configured to classify the change in resistance ascorresponding to a magnitude of the deforming load.

In another embodiment, a sensor for occupant monitoring in a vehicleincludes a flexible substrate in proximity to a deformable seat surface.A plurality of conductive traces are positioned on the flexiblesubstrate, and the conductive traces are configured to bend in responseto a deforming load that is applied to the deformable seat surface andtransferred through the deformable seat surface to at least a portion ofthe conductive traces. At least a first of the conductive traces form aresistive sensor circuit on a first side of the flexible substrate,wherein the resistive sensor circuit has an electrical resistance thatfluctuates according to a degree of deformation of the conductive inktrace in response to the bend. A voltage source is in electricalcommunication with a first end of the conductive traces. A computer hasa processor and memory in data communication with the opposite end ofthe conductive ink traces, wherein the computer measures a change inresistance of the resistive sensor circuit due to the bend, and thecomputer is configured to classify the change in resistance ascorresponding to a magnitude of the deforming load.

BRIEF DESCRIPTION OF THE DRAWINGS

The components in the drawings are not necessarily to scale relative toeach other. Like reference numerals designate corresponding partsthroughout the several views.

FIG. 1A illustrates a plan view of a first side of a sensor substrateaccording to one implementation of this disclosure.

FIG. 1B illustrates a plan view of a second side of a sensor substrateaccording to one implementation of this disclosure.

FIG. 2 illustrates a front perspective view of an assembled sensorsubstrate according to one embodiment of this disclosure.

FIG. 3 illustrates a rear plan view of an assembled sensor substrateaccording to one embodiment of this disclosure.

FIG. 4A illustrates a rearward perspective view of a cross sectionacross the z-axis (thickness) of an assembled sensor substrate accordingto one embodiment of this disclosure.

FIG. 4B illustrates a frontward perspective view of a cross sectionacross the z-axis (thickness) of an assembled sensor substrate accordingto one embodiment of this disclosure.

FIG. 5 illustrates a perspective view of a first example of layers ofcircuit patterns printed onto a sensor mat according to oneimplementation of this disclosure.

FIG. 6A illustrates a perspective view of an example circuit patternprinted onto a sensor mat and subject to a force thereon according toone implementation.

FIG. 6B illustrates a perspective view of the example circuit pattern ofFIG. 6A printed onto a sensor mat with the force removed according toone implementation.

FIG. 6C illustrates a plan transparent view of layers of circuitpatterns printed onto a sensor mat according to one implementation ofthis disclosure.

FIG. 7 illustrates a schematic diagram of a sensor substrate havinginterleaved conductors for sensing and shielding operations according tothe embodiments herein.

FIG. 8A illustrates a side plan view of a vehicle seat having a sensoras described herein installed below the seat surface.

FIG. 8B illustrates a side plan view of a vehicle seat having a sensoras described herein installed below the seat surface.

FIG. 9 illustrates an example embodiment of a sensor as described hereininstalled in an arm rest of a vehicle.

FIG. 10 illustrates a schematic view of a computer environment in whichembodiments of this disclosure are implemented.

DETAILED DESCRIPTION

Apparatuses, systems and methods of electronically sensing occupants andother objects within a vehicle, along with appropriate shieldingmechanisms to account for electrical interference, are disclosed herein.The concepts described herein are equally applicable to occupant andobject sensing technologies that can be placed within or proximate toany vehicle component that would benefit from electronic sensing,associated shielding functions, and computerized analysis techniquesthat provide control data to vehicle data management systems. Terms usedin this disclosure, therefore, are intended to imply their broadestmeaning. For example, references to “vehicles” include all forms oftransportation apparatuses in which occupants move from one destinationto another. In fact, certain physical implementations of a sensingsystem may be useful in numerous kinds of electronic sensingenvironments, and the term “capacitive” sensing is not intended to bethe sole technology sector that can utilize the structures describedbelow.

One non-limiting implementation of capacitive sensing technologies is asensor system shown in FIGS. 1A and 1B that includes a sensor circuitconstruction 190 configured for placement in or on multiple structureswithin the interior of a vehicle. As illustrated in FIG. 1A, a circuitconstruction 190 may include a base substrate, layer or sheet 100 thatallows for constructing a resistive sensor circuit 122 and a capacitivesensor circuit 124 on a first side 110 of the substrate 100. A secondside 112 of the substrate 100 supports a shield circuit 126 thereon suchthat the sensing and shielding operations of the overall sensor systeminclude a minimal number of layers to install. In fact, by utilizingprinting operations and conductive ink products, both of the sensorcircuits 122, 124 and the shield circuit 126 can be formed on oppositesides 110, 112 of a single layer (i.e., a single substrate 100).

Another way to describe the embodiment of FIGS. 1A and 1B is that acircuit construction 190 for placing in a sensing system within avehicle includes a non-conductive sheet 100 having a first planar face140 and a second planar face 142, corresponding to the respective firstside 110 and second side 112. Respective conductive traces 132, 134, and136 are printed onto and/or otherwise adhered to the first planar face140 and the second planar face 142 of the substrate 100. In oneembodiment described below, the conductive traces may be screen printedonto the opposite sides 110, 112 of the substrate in a silver polymerink as illustrated in FIGS. 1A and 1B. In non-limiting examples, thesubstrate 100 may be formed as a sheet of a thin nylon fabric that isbetween 0.10 mm and 0.2 mm thick.

The conductive traces described herein may be between 0.008 mm and 0.015mm thick, with endpoints of the range included. In fact, the conductivetraces may within a range of 0.008 mm to 0.020 mm thick and provideappropriate functionality.

One non-limiting goal of the described embodiments is to provide asensing and shielding structure that can be positioned withinhard-to-fit vehicle components of numerous shapes, contours, and sizesinside a vehicle. To accomplish this goal, the substrate 100 and theconductive traces 132, 134, and 136 each comprise flexible compositionswith a mutual resilience that allows the substrate and the traces tostretch and contract in conjunction with one another. The term mutualresilience is intended for descriptive purposes only, but in general,the extent of resilience of the substrate 100 and the correspondingresilience of the electrically conductive traces 132, 134, and 136 areengineered to maintain structural and electrical continuity of theconductive traces in the presence of deforming forces being exerted uponthe sheet and then released in repetitive fashion. The substrate 100 andthe conductive traces 132, 134, and 136 are designed with stretchingparameters that overlap so that deforming forces cannot stretch orcontract the overall circuit construction 190 in a manner that breaksstretching limits for either or both of the sheet or substrate 100 andthe conductive traces 132, 134, and 136 thereon. In other words, thesubstrate 100 can be molded, shaped, folded, and most importantly,stretched to comply with design considerations without breaking thecircuits formed by the conductive traces 132, 134, and 136. The sheetand the conductive traces are configured to withstand deforming forcesthat stretch a dimension of the sheet in any direction by an amountbetween 2 percent and 10 percent.

FIGS. 2 and 3 illustrate embodiments of this disclosure by which theconductive traces 132, 134, and 136 may be configured as bendableconductive traces that stretch, compress, and bend in response to loadforces (L) exerted thereon. The bendable conductive traces also exhibitcorresponding electrical and electromagnetic properties in accordancewith the bend. As shown by circuit test equipment in FIGS. 6A and 6B,the bendable conductive traces 141 may be positioned on a substrate 100and then used for identifying changes in the bendable conductive trace'sresistance, current flow, capacitive effects, and other electrical orelectromagnetic responses to outside loading forces 143. The bendableconductive traces 141 may be installed as noted above to form a sensingsystem using circuit construction 190 on a substrate 100 and includes aresistive sensor trace 128 and a capacitive sensor trace 129 on one sideand a shield sensor trace 131 on an opposite side.

FIGS. 1-3 illustrate that conductive traces 132, 134, and 136 which canbe configured as bendable conductive traces 141 on opposite sides of thesubstrate 100, as well as the substrate, or sheet itself, can havelength, width and height dimensions along x, y, and z axes respectively.Accordingly, the mutual resilience between the non-conductive substrate100 and the respective conductive traces 132, 134, and 136 on oppositesides 110, 112 of the substrate 100 give the circuit construction 190 amemory shape effect, allowing the entire circuit construction 190 to besubject to stretching, contracting, or other deforming forces along theaxes without breaking the conductive traces and the resulting shieldingand sensing circuits.

FIGS. 4A and 4B are cross section illustrations of a substrate 100,illustrated as being transparent for example purposes, and the crosssections are taken through the z-axis (i.e, across the thickness of thesubstrate 100). FIGS. 4A and 4B, therefore, show that the conductivetraces 132 for the resistive sensor circuit 122 and conductive traces134 for the capacitive sensor circuit 124 define a first pattern 71(resistive) and a second pattern 72 (capacitive) on the first side 110of the non-conductive substrate 100 and a third pattern 81 (shielding)on the second side 112 of the sheet 100. In other embodiments, thepatterns 71, 72, 81 may be similar or even identical. In onenon-limiting example, the conductive traces 132, 134, and 136 on theopposite faces of the sheet substrate 100 operate similarly to separatesensor mats and shielding mats of multi-layered capacitive sensingdevices, but with much more flexibility in design and more possible usesthat require space saving efficiency not seen in prior devices.

In one non-limiting embodiment, FIG. 5 illustrates an exploded view of asensor system circuit construction 190 according to this disclosure. Theexploded view is not limiting of this disclosure but does illustrate oneexample implementation of how printed metallic (e.g., mesh-like) layersfit on opposite sides of the substrate 100 to accomplish the sensingoperations, shielding functions, and even heating options necessary foroccupant detection and occupant classification. The circuits 122, 124,126 and metallic conductive traces 132, 134, 136 of the figures are notexclusive, and as shown in FIG. 7 , in some embodiments, the conductivetraces 701A, 701B may be interleaved without touching for particularcircuits on either side of the substrate 100.

The exploded view of FIG. 5 illustrates how metallic patterns 71, 72, 81on opposite sides 110, 112 of the non-conductive sheet 100 can form therequisite sensing structures. In one non-limiting assembly, the sensor500 may include the substrate 100, which is stretchable and electricallyinsulating as described above. On a first side 110, two circuit patterns71, 72 may be arranged by printing conductive traces 132, 134 which maybe similar to bendable conductive ink traces 141 of FIGS. 6A and 6B andconfigured as a respective resistive sensor circuit 122 and capacitivesensor circuit 124 on the substrate 100. On the second side 112, anotherpattern 81 of conductive ink traces 136 is formed for the shieldingeffect described above in a shield circuit 126. In the example of FIG. 5, the resistive, capacitive, and shielding ink traces have more than onelayer. As shown, the substrate 100 supports a resistive sensor assembly151 that incorporates at least two layers—a highly conductive deposit153A and a moderately conductive second deposit 153B. The resistivity ofeach deposit 153A, 153B can be tailored to match specificationsnecessary for the use at hand. Also, on the first side 110 of thesubstrate 100, a capacitive sensor assembly 161 includes multiple layersformed on the first side 110, alongside but without touching theresistive sensor assembly 151. In another embodiment, a single trace maybe used as the capacitive sensor and the resistive sensor in the samecircuit. The capacitive sensor assembly includes a conductive patternedsection 155A and an overlay section 155B. In one embodiment, theconductive patterned section 155A is a highly conductive pattern and theoverlay section 155B is only moderately conductive. As noted above, thesecond side 112 of the substrate 110 also includes the shielding circuit126 that can also incorporate a capacitive shield assembly 171, which,like the corresponding opposite layers, may have more than one layer inthe shield assembly 171. FIG. 5 illustrates that capacitive shieldassembly 171 has a highly conductive trace 136 forming a conductivelypatterned section 157A and a moderately conductive overlay layer 157B.

As noted, one aspect of a circuit construction 190 according to thisdisclosure is the ease with which the circuit construction 190 can bestretched for molding into a particular shape for a given application.In this regard, the non-conductive sheet 100 may be described as anelastic memory sheet having a sheet width dimension, sheet thicknessdimension and a sheet length dimension along respective axes. Similarly,each of the patterns 71, 72, 81 have a corresponding, respective patternwidth dimension and a respective pattern length dimension alongrespective axes. In one example that is not limiting of this disclosure,the sheet width dimension and the respective pattern width dimensionsstretch and contract by an amount of 2 percent to 10 percent,simultaneously, in the presence of the deforming forces along acorresponding axis. Similarly, the sheet length dimension and saidrespective pattern length dimensions stretch and contract by an amountof 2 percent to 10 percent, simultaneously in the presence of thedeforming forces along the other axis. Deforming forces on the sheet mayinclude at least one of tensile forces, compressive forces, shearforces, and combinations thereof, such as forces used for installing ormolding the circuit construction 190 for placement on or within acorresponding vehicle component (e.g., around a steering wheel, along anA-pillar or B-pillar, in a seat, or even on an accessory such as a glovecompartment door, a parking brake, a visor, a head rest, or a dash boardaccessory of the vehicle).

The conductive traces 132, 134, and 136 of the circuit construction 190form respective sensing circuits and shielding circuits on a single basesheet or substrate 100. The non-conductive nature of the sheet 100prevents short circuits through the sheet and controls both a sensingcapacitance and parasitic capacitance levels in a sensing operation. Inone embodiment, the conductive traces 132, 134, and 136 are formed byprinting, preferably, but not exclusively, screen printing, theconductive traces, and then either curing the conductive traces at apre-defined temperature or letting the conductive traces dry on eachside of the sheet before use. In this regard, all of the conductivetraces on the opposite sides of the sheet form a solidified derivativestructure of a fluidic and printable composition, such as a conductiveink. In one embodiment, the solidified derivative structure is astretchable conductive ink, such as a silver polymer ink shown in FIG. 1. Other conductive traces (wiring, films, polymers, semiconductors,etc.) are also within the scope of this disclosure as technologiesenable the same.

As noted, the circuit construction 190 is used for electrical sensingsystems in a vehicle and may incorporate a base layer 100 in the form ofa non-conductive sheet that is also flexible, conducive to formingmultiple shapes, and can be stretched for placement on or within avehicle component. The non-conductive sheet 100 may be a film thatsupports the conductive traces 132, 134, and 136 without allowing anyshort circuits through the sheets. The sheet may be a plastic film andmay be selected from numerous polymeric materials including filmsselected from polyethylene terephthalate (PET), polyethylene naphthalate(PEN), polyimide plastics (PI), and combinations thereof. Other sheetsmay be more conducive to stretching as described above and be formed ofa plastic film comprising a thermoplastic polyurethane film. The plasticfilm is impervious to a conductive ink used to form the conductivetraces. In other embodiments, the non-conductive sheet may be a fabric,including at least one of woven fabrics, non-woven fabrics, andcombinations thereof. For fabrics that would ordinarily absorb theconductive inks and cause bleed-through problems (and short circuitsbetween the opposite sides 110, 112), the fabric may include a surfacefinish that enables screen printing and is resistant to the fabricabsorbing a conductive ink used to form the respective traces. Toaccomplish a dual sided circuit on the substrate, fabric or a film has asufficient surface energy to promote adhesion of the conductive traces.

The circuit construction 190 used for sensing circuits 122, 124 andshielding circuits 126 as discussed herein may be configured formanufacturing with printing processes that form the conductive tracesthereon. The circuit construction for sensing and shielding may be onthe same side of a single substrate or on opposite sides of a singlesubstrate. In a method of forming the circuits on opposite sides of thesame substrate 100, steps include applying respective fiducials to afirst face 110 and a second face 112 of a flexible fabric, sheet, orfilm layer (base material substrate 100) to guide a printing process Thesheet is held in place at a constant tension and maintained in stabledimensions for printing a first conductive trace 132 of a first pattern71 on the first face 110 of the flexible base material, or substrate100. The method further includes printing a second conductive trace 134of a second pattern 72 on the opposite side 112 of the flexible basematerial, wherein the printing is completed according to a placement ofthe fiducials. The first and second patterns 71, 72 can be entirelydistinct and non-overlapping from one another as shown in the figures,or the patterns can be similar or even identical so far as a generalpattern is concerned. In one method, the fiducials are screen printfiducials and the printing is screen printing with a conductive ink.Prior to printing the second conductive trace, a manufacturing methodincludes applying at least one of the respective fiducials to the secondface and screen printing the second conductive trace. Prior to applyingthe at least one of the respective fiducials, a step includes drying thefirst conductive trace and turning over the flexible fabric for furtherprinting. Either side of the substrate 100 may also be printedaccordingly with a third conductive trace, such as the above notedresistive sensor trace. In one optional step, the method furtherincludes applying a carbon polymer or other moderately conductivecoating to at least one side of the flexible fabric. Upon drying or firmplacement of the first pattern 71 (resistive) and the second pattern 72(capacitive), the same kinds of steps may proceed on the opposite side112 to form the shielding layer traces 136 and the shielding pattern 81.

In a method of forming the circuits on one side of the same substrate100, steps include applying respective fiducials to a first face 110 ofa flexible fabric, sheet, or film layer (base material substrate 100) toguide a printing process. Next, the sheet is held in place at a constanttension and maintained in stable dimensions for printing a firstconductive trace 132 of a first pattern 71 on the first face 110 of theflexible base material, or substrate 100. The method further includesprinting a second conductive trace 134 of a second pattern 72 on thesame side 110 of the flexible base material, wherein the printing iscompleted according to a placement of the fiducials. The first andsecond patterns 71, 72 can be entirely distinct and non-overlapping fromone another as shown in the figures, or the patterns can be similar oreven identical, without overlapping on the same side, so far as ageneral pattern is concerned. In one method, the fiducials are screenprint fiducials and the printing is screen printing with a conductiveink. Prior to printing the second conductive trace, a manufacturingmethod includes repositioning and reapplying at least one of therespective fiducials to the first face and screen printing the secondconductive trace. Prior to applying the at least one of the respectivefiducials, a step includes drying the first conductive trace and turningthe flexible fabric for further printing. The second side 112 of thesubstrate 100 may also be printed accordingly with a third conductivetrace 136. The respective fiducials define the third conductive trace asa plurality of zones for shielding the resistive sensor circuit 122 andthe capacitive sensor circuit 124 of a vehicle installed sensor system.In one optional step, the method further includes applying a carbonpolymer or other moderately conductive coating to at least one side ofthe flexible fabric. Upon drying or firm placement of the first pattern71 (resistive) and the second pattern 72 (capacitive), the same kinds ofsteps may proceed on the opposite side 112 to form the shielding layertraces 136 and the shielding pattern 81.

Numerous installations of the sensor circuit construction 190 areavailable for use in a vehicle. FIGS. 8A and 8B illustrate exampleembodiments in which the sensor of this disclosure is installed in avehicle seat assembly. As noted above and shown in FIG. 6A, theconductive ink traces 132, 134, and 136 are configured to bend inresponse to a deforming load (L) 143 applied to at least a portion ofthe conductive ink trace, and at least the resistive conductive inktrace 132 has an electrical resistance that fluctuates according to adegree of deformation of the conductive ink trace in response to thebend 143, as shown in FIGS. 6A and 6B. The deforming load may be atensile force that stretches that conductive ink trace across the bendand/or a compressive force on the conductive ink trace due to the bend.The seat assembly 810 and the flexible substrate 100 and the conductiveink traces 132, 134, 136 are configured to withstand a respectivedeforming load that stretches or compresses across all dimensions of theflexible substrate and/or a respective conductive ink trace. Thisdisclosure imposes no limits on the loading forces, such as the weightof an occupant, in magnitude or direction, other than naturalconsiderations for the materials in use and the capacity of a subjectvehicle.

The deforming load (L) may be applied from an exposed surface 813 of theseat assembly 810 through the deformable seat surface and toward theseat frame 819. For example, the deforming load may be a weight of anoccupant 812 on the deformable seat surface 813. In many vehicleinstallations, the deformable seat surface is a porous cushion 815 of anoriginal shape, and the porous cushion exhibits a structural memory thatdeforms toward the seat frame 819 in the presence of the deforming load.The seat cushion reverts to the original shape in the absence of thedeforming load. The porous cushion exhibits a maximum degree ofdeformation for a respective magnitude of the deforming load that isless than the corresponding maximum degree of deformation exhibited bythe flexible substrate 100 and the conductive ink traces 132, 134, and136 under a same deforming load. The seat assembly 10 may, furthermore,include a plurality of the conductive ink traces 132, 134, 136 onrespective flexible substrates 100 attached to numerous areas on thedeformable seat surface, creating different zones for respectivelyidentifiable data collection. The different positions for a substrate100 having conductive ink traces 132, 134, 136 thereon exhibitrespective tensile deformation or compressive deformation on each of theconductive ink traces in the presence of an occupant 812 on thedeformable seat surface 813.

In one aspect of this disclosure, the tensile deformation andcompressive deformation adjust the electrical resistance of therespective conductive ink traces, particularly the resistive sensorcircuit 122 in accordance with the positions. The presence of anoccupant, as well as the shape, size and location of the occupant, alsoinfluences the electric fields around the capacitive sensor circuits124. These changes in physical parameters in each of the circuits of thesensor assembly 190 can be monitored to detect weight, occupantpresence, the kind of occupant or object in a vehicle, and the like. Inone embodiment, a voltage source attached to a first end of any one ofthe conductive ink traces and a computer 1000 having a processor 1002and memory 1004 attached to the opposite end of the conductive inktraces, allow a computer 1000 to measure a change in resistance and/orcapacitance of any given conductive ink trace due to the presence of theoccupant. For a change in resistance on the resistive sensor assembly151, the resistances may be processed to identify an occupant, a weightor size of an occupant, or whether the occupant is a living, dynamicallymoving object or a static object across a time period. This data canthen be used to program safety features in a vehicle, such as, but notlimited to, control systems for air bag activation, ignition start, anduse of electronic accessories. The embodiments of a conductive trace ona flexible substrate as described herein are not limited only to seatsand steering wheels, but may be installed on other vehicle components.In some embodiments, the installation 915 may be within an arm rest 900(e.g., FIG. 9 ), a head rest, storage compartment lid, and othersurfaces accessible from the seat assembly.

A substrate 100 with a conductive ink trace 132, 134, 136 as disclosedin this description may serve dual purposes, including heating subjectsurfaces in a vehicle when the resistance in the conductive trace 132,the resistive sensor layer, is sufficiently high. In the heatingembodiments, a power source connected to the electronic control unit 830is configured for selectively generating an electrical current throughone or more resistive sensors to heat the circuit and serve as a seatheater.

In other embodiments, the shielding circuit may be configured as a partof a seat heater embodiment in which a voltage signal through one ormore shielding circuits generates heat for the seat heating operation.An electronic control unit 830 may be used to alternate heating signalswith shielding signals through the sensor assembly . The heating currentis greater than a shielding current. For example, the heating current isaround 4 to around 8 amperes, which is sufficient for producing heat forthe seat, and the shielding current is less than about 200 milliamperes,which is sufficient for shielding the sensor mat from the seat frame,according to some implementations.

As shown in FIG. 8B, the installation of the substrate 100 may be moreappropriately placed across portions of a seat frame 819 to sense anoccupant presence relative to a seat position. In this installation, thesubstrate 100 operates as a strain gauge and exhibits changes inresistance and capacitance effects due to load forces thereon. This kindof data is also useful in monitoring occupants within a vehicle,particularly in terms of proper seat belt use.

As noted above, the conductive traces 132, 134, 136 on opposite sides ofthe substrate 100 can be connected to electrical circuits and used forcapacitive sensing and shielding functions in the vehicle as part ofoccupant monitoring, safety systems, or accessory control systems in avehicle. The shielding function may be illustrated as shown in FIG. 8Awhen a sensor of this disclosure is assembled within the seat cushionarea and proximate a seat heater. In some non-limiting embodiments andonly for example herein, a circuit construction 190 having a sensingcircuit and a shielding circuit thereon may be used to shield thecapacitive sensor circuit 124 and its layers from parasitic capacitanceand deleterious field effects of the seat heater 802. By keeping theshield circuit 126 directly adjacent the sensor circuits 122, 124, thedistance fluctuation between the two circuits is controlled by a knownsheet thickness that does not vary widely because opportunities forthermal expansion and contraction are minimized.

An electronic control unit (ECU) 830, which is shown in FIGS. 8A and 8B,is in electronic communication with the seat heater shown in the figure,the sensor circuits 122, 124, the shield circuit 126, and one or moreother vehicle systems (not shown). In particular, sensor return wiresextend between the ECU 830 and each sensing circuit 122, 124,respectively and conveniently connect to the ECU 830 and various vehiclesystems via a wire harness in the seat assembly. The ECU includes aprocessor and a power source.

In addition to being configured to detect presence of a driver's body,the sensing assemblies described herein may also be configured to detectvarious types of user input in each respective sensing zone, such as agrip, swipe motion, tap motion, etc., from signals received from thesensor mat. For example, by using a multi-zone sensor mat with sensingloops disposed in specific areas, the sensor mat may be configured fordetecting the location of different occupants' and their body parts,seat belts, and the like The embodiments are not limited to only sensinga human, other animal or a given body part, but the circuit construction190 has appropriate circuits to sense any conductive object whether astatic, inanimate object that causes an electrical response in thecircuits of the substrate or a living dynamic animal or human.

Embodiments of this disclosure include production and use of sensorcircuit construction 190 and/or a sensor 500 alone. The sensor 500 maybe utilized in numerous vehicle components or even in other industriesall together. In one sensor embodiment, a sensor circuit construction190 for occupant monitoring in a vehicle includes a flexible substrate100 that is resilient to a deforming load thereon. A plurality ofconductive traces 132, 134, 136 are on the flexible substrate 100, andthe conductive traces are configured for bending in response to thedeforming load applied to the flexible substrate 100 and the conductivetraces 132, 134, 136. A resistive sensor circuit 122 is on a first side110 of the flexible substrate, and the resistive sensor circuit 122includes a respective set of the conductive traces, wherein theresistive sensor circuit has an electrical resistance that fluctuatesaccording to a degree of deformation of the respective set of theconductive traces in response to the bending. In non-limitingembodiments, the substrate 100 includes a nonconductive substrate oreven any single layer of insulating material. Other embodiments utilizea flexible substrate in the form of a non-conductive film. Thenon-conductive film may include at least one of polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), polyimide plastics(PI), a thermoplastic polyurethane, and combinations thereof.

In addition to the resistive sensor circuit 122 on the first side 110 ofthe flexible substrate, the sensor may have a capacitive sensor circuit124 formed of a second set of conductive traces on the first side 110 ofthe flexible substrate 100. For certain non-limiting installations, thesensor 500 may further include a capacitive shield circuit 126 formed ofa third set of the conductive traces on the second side 112 of thesubstrate 100. The resistive sensor circuit 122, the capacitive sensorcircuit 124, and the capacitive shield circuit 126 include appropriaterespective circuit connections and connection assemblies at a first endof at least one of said conductive traces and at an opposite end of saidat least one of said conductive traces.

The sensor 500, along with its resistive sensor circuit 122, capacitivesensor circuit 124, and capacitive shield circuit 126, may include aplurality of conductive traces 132, 134, 136, and the conductive tracesmay be conductive ink traces. As described above, the plurality ofconductive traces may be formed by screen printing processes to yieldscreen printed conductive traces. The plurality of conductive traces mayinclude, without limitation, silver polymer ink. This disclosureincludes numerous materials and methods of depositing and/or adheringthe conductive traces 132, 134, 136 to the substrate. In someembodiments, the substrate 100 and the conductive traces 132, 134, 136have a mutual resilience configured to allow the substrate and theconductive traces to stretch and contract in conjunction with oneanother without breaking the conductive traces. The physical propertiesof the conductive traces, materials used to form the conductive tracesand the substrate, and the methods of manufacture of the sensor may beengineered to ensure that the substrate and the conductive traces havecommon physical properties, such as overlapping stretching performanceparameters and deformation profiles in the presence of load forces. Inthis way, overlapping physical parameters, including stretchingparameters, may provide a mutual resilience to deformation loads. In onenon-limiting embodiment, the substrate and the conductive traces have amutual resilience to withstand deforming forces that stretch a dimensionof the sheet in any direction by an amount between 2 percent and 10percent of an original dimension.

As shown in one example of FIG. 5 , a sensor 500, includes an insulatingsubstrate 100 that is flexible, stretchable, and/or deformable inaccordance with this disclosure. The sensor 500 has a resistive sensorassembly 151 formed of a first set of conductive traces 153A, 153B on afirst side 110 of the flexible substrate 100, a capacitive sensorcircuit 161 formed of a second set of the conductive traces 155A, 155Bon the first side 110 of the flexible substrate 100 and a capacitiveshield circuit 171 formed of a third set of the conductive traces 157A,157B on a second side 112 of the substrate. The resistive sensor circuitassembly 151, the capacitive sensor circuit assembly 161, and thecapacitive shield circuit assembly 171 may, optionally, each have aplurality of layers or be formed of a single layer. In the non-limitingembodiment of FIG. 5 , the resistive sensor circuit 151 includes aresistive circuit assembly having a highly conductive deposit layer 71in the form of conductive trace 153A of a first conductivity and amoderately conductive deposit layer 73 in the form of conductive trace153B of a second conductivity that is lower than the first conductivity.The capacitive sensor circuit 161 may include a multiple layer assemblyformed alongside but without touching the resistive sensor circuit 151.The capacitive sensor circuit 161 includes a conductive patternedsection 155A and an overlay section 155B. The conductive patternedsection 155A includes a highly conductive pattern 72 having a respectiveconductivity, and the overlay section 155B includes a moderateconductivity pattern 74 that is lower than the respective conductivityof the highly conductive pattern 72. On the second side of the substrate112, the capacitive shield circuit 171 includes a highly conductivetrace 157A having a respective trace layer of a respectively highconductivity pattern 81 and an overlay layer 157B of a respectivelymoderate conductivity pattern 83 that is lower than the respectivelyhigh conductivity.

Furthermore, in sensor circuits having multiple zones, signals carriedby sensor return wires associated with each sensing zone may generatenoise in the sensing loops or sensor return wires associated withadjacent zones when the wires are too close to each other. This noisedecreases the ability of the sensor mat to detect presence of anoccupant adjacent one or more sensing zones. In addition, cross talkfrom a sensor return wire from one zone that crosses over another zonemay result in unintended detection from another zone. Accordingly,various implementations described herein provide for shielding around atleast a portion of the sensor return wires that may be disposed adjacentanother sensing zone or sensor return wire to isolate the signal(s)carried by the sensor return wire(s).

Furthermore, biometric type sensors may be disposed in the vehicle towork in conjunction with hand sensing through the steering wheel usingnon-biometric type sensors. These biometric sensors may be disposed onthe steering wheel or elsewhere in the vehicle. Examples of thesebiometric type sensors include retina detection, heart rate monitoring,arousal state monitoring, and driver detection (e.g., in a vehicleseat).

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art. Methods and materials similar or equivalent to those describedherein can be used in the practice or testing of the present disclosure.As used in the specification, and in the appended claims, the singularforms “a,” “an,” and “the” include plural referents unless the contextclearly dictates otherwise. The term “comprising” and variations thereofas used herein is used synonymously with the term “including” andvariations thereof and are open, non-limiting terms. Whileimplementations will be described for steering wheel hand detectionsystems, it will become evident to those skilled in the art that theimplementations are not limited thereto.

As utilized herein, the terms “approximately,” “about,” “substantially”,and similar terms are intended to have a broad meaning in harmony withthe common and accepted usage by those of ordinary skill in the art towhich the subject matter of this disclosure pertains. It should beunderstood by those of skill in the art who review this disclosure thatthese terms are intended to allow a description of certain featuresdescribed and claimed without restricting the scope of these features tothe precise numerical ranges provided. Accordingly, these terms shouldbe interpreted as indicating that insubstantial or inconsequentialmodifications or alterations of the subject matter described and claimedare considered to be within the scope of the invention as recited in theappended claims.

It should be noted that the term “exemplary” as used herein to describevarious embodiments is intended to indicate that such embodiments arepossible examples, representations, and/or illustrations of possibleembodiments (and such term is not intended to connote that suchembodiments are necessarily extraordinary or superlative examples).

The terms “coupled,” “connected,” and the like as used herein mean thejoining of two members directly or indirectly to one another. Suchjoining may be stationary (e.g., permanent) or moveable (e.g., removableor releasable). Such joining may be achieved with the two members or thetwo members and any additional intermediate members being integrallyformed as a single unitary body with one another or with the two membersor the two members and any additional intermediate members beingattached to one another.

References herein to the positions of elements (e.g., “top,” “bottom,”“above,” “below,” etc.) are merely used to describe the orientation ofvarious elements in the FIGURES. It should be noted that the orientationof various elements may differ according to other exemplary embodiments,and that such variations are intended to be encompassed by the presentdisclosure.

It is important to note that the construction and arrangement of thesensing system as shown in the various exemplary embodiments isillustrative only. Although only a few embodiments have been describedin detail in this disclosure, those skilled in the art who review thisdisclosure will readily appreciate that many modifications are possible(e.g., variations in sizes, dimensions, structures, shapes andproportions of the various elements, values of parameters, mounting orlayering arrangements, use of materials, colors, orientations, etc.)without materially departing from the novel teachings and advantages ofthe subject matter described herein. For example, elements shown asintegrally formed may be constructed of multiple parts or elements, theposition of elements may be reversed or otherwise varied, and the natureor number of discrete elements or positions may be altered or varied.The order or sequence of any process or method steps may be varied orre-sequenced according to alternative embodiments. Other substitutions,modifications, changes and omissions may also be made in the design,operating conditions and arrangement of the various exemplaryembodiments without departing from the scope of the present embodiments.

The figures utilize an exemplary computing environment in which exampleembodiments and aspects may be implemented. The computing deviceenvironment is only one example of a suitable computing environment andis not intended to suggest any limitation as to the scope of use orfunctionality.

Numerous other general purpose or special purpose computing devicesenvironments or configurations may be used. Examples of well-knowncomputing devices, environments, and/or configurations that may besuitable for use include, but are not limited to, personal computers,server computers, handheld or laptop devices, multiprocessor systems,microprocessor-based systems, network personal computers (PCs),minicomputers, mainframe computers, embedded systems, distributedcomputing environments that include any of the above systems or devices,and the like.

Computer-executable instructions, such as program modules, beingexecuted by a computer may be used. Generally, program modules includeroutines, programs, objects, components, data structures, etc. thatperform particular tasks or implement particular abstract data types.Distributed computing environments may be used where tasks are performedby remote processing devices that are linked through a communicationsnetwork or other data transmission medium. In a distributed computingenvironment, program modules and other data may be located in both localand remote computer storage media including memory storage devices.

In its most basic configuration, a computing device typically includesat least one processing unit and memory. Depending on the exactconfiguration and type of computing device, memory may be volatile (suchas random access memory (RAM)), non-volatile (such as read-only memory(ROM), flash memory, etc.), or some combination of the two.

Computing devices may have additional features/functionality. Forexample, computing device may include additional storage (removableand/or non-removable) including, but not limited to, magnetic or opticaldisks or tape. Such additional storage is illustrated in FIG. 10 byremovable storage and non-removable storage.

Computing device typically includes a variety of computer readablemedia. Computer readable media can be any available media that can beaccessed by the device and includes both volatile and non-volatilemedia, removable and non-removable media.

Computer storage media include volatile and non-volatile, and removableand non-removable media implemented in any method or technology forstorage of information such as computer readable instructions, datastructures, program modules or other data. Memory, removable storage,and non-removable storage are all examples of computer storage media.Computer storage media include, but are not limited to, RAM, ROM,electrically erasable program read-only memory (EEPROM), flash memory orother memory technology, CD-ROM, digital versatile disks (DVD) or otheroptical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which canbe used to store the desired information and which can be accessed bycomputing device. Any such computer storage media may be part ofcomputing device.

FIG. 10 illustrates one example computing environment that may implementdata processing necessary in the embodiments of this disclosure.Computing device 1000 may contain communication connection(s) that allowthe device to communicate with other devices. Computing device may alsohave input device(s) such as a keyboard, mouse, pen, voice input device,touch input device, etc. Output device(s) such as a display, speakers,printer, etc. may also be included. All these devices are well known inthe art and need not be discussed at length here.

It should be understood that the various techniques described herein maybe implemented in connection with hardware components or softwarecomponents or, where appropriate, with a combination of both.Illustrative types of hardware components that can be used includeField-programmable Gate Arrays (FPGAs), Application-specific IntegratedCircuits (ASICs), Application-specific Standard Products (ASSPs),System-on-a-chip systems (SOCs), Complex Programmable Logic Devices(CPLDs), etc. The methods and apparatus of the presently disclosedsubject matter, or certain aspects or portions thereof, may take theform of program code (i.e., instructions) embodied in tangible media,such as CD-ROMs, hard drives, or any other machine-readable storagemedium where, when the program code is loaded into and executed by amachine, such as a computer, the machine becomes an apparatus forpracticing the presently disclosed subject matter.

FIG. 10 illustrates an example of a computer environment 1000 in whichthe above described electronic control unit 830 operates. In general,the ECU 830 is designated to control sensing and shielding operations asdescribed above and process signals, whether power signals or datasignals, received from and/or provided to the shield circuit and thesensor circuits. With the computer hardware 1006 including anappropriate processor 1002 and memory 1004, the ECU 830 can beconfigured with computer implemented software to ensure that thecircuits in the overall shielding, sensing, and heating systems of thisdisclosure operate for the purposes described above. In one sense, theECU 830 may be local to the circuit construction 190 of this disclosure,and in certain non-limiting embodiments, may include a somewhat basicconfiguration that is tailored to control only the sensing, shielding,and heating circuits in a substrate installation. This local ECU 830 mayalso be connected to a more global vehicle control system thatimplements a plurality of vehicle systems and accessories with morepowerful hardware configurations, generally designated as a computerizedvehicle data management system. It is notable that a vehicle-wide datamanagement system will likely include system memory and processors, butwill also incorporate more sophisticated kinds of memory devices,including removable storage 1008, non-removable storage 1010, multipleI/O connections 1012, 1014 for input devices and a network interfacecontroller 1016 for diverse data communications throughout the vehicle.In this regard, the various components of computerized systems utilizedfor sensing technology herein are selected to transfer data or evenpower signals between source devices and recipient devices according tovarious implementations that tailored to the use at hand. In particular,the embodiments of this disclosure may utilize any kind of computeroperations capable of network connection, including accessories such ashuman machine interface systems (e.g., touch pad(s), touch sensitiveareas on a display, and/or switches for interfacing with one or morecomponents on a data communications network handling occupant sensingand corresponding user communications).

Although exemplary implementations may refer to utilizing aspects of thepresently disclosed subject matter in the context of one or morestand-alone computer systems, the subject matter is not so limited, butrather may be implemented in connection with any computing environment,such as a network or distributed computing environment. Still further,aspects of the presently disclosed subject matter may be implemented inor across a plurality of processing chips or devices, and storage maysimilarly be configured across a plurality of devices.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described above.Rather, the specific features and acts described above are disclosed asexample forms of implementing the claims.

The invention claimed is:
 1. A sensor for occupant monitoring in a vehicle, comprising: a flexible substrate that is resilient to a deforming load thereon; a plurality of conductive traces on the flexible substrate, said conductive traces configured for bending in response to the deforming load applied to the flexible substrate and the conductive traces; and a resistive sensor circuit on a first side of said flexible substrate, the resistive sensor circuit comprising a respective set of the conductive traces, wherein said resistive sensor circuit has an electrical resistance that fluctuates according to a degree of deformation of the respective set of the conductive traces in response to the bending.
 2. The sensor of claim 1, wherein said plurality of conductive traces comprise conductive ink traces.
 3. The sensor of claim 1, wherein said plurality of conductive traces comprise screen printed conductive traces.
 4. The sensor of claim 1, wherein said plurality of conductive traces comprise silver polymer ink.
 5. The sensor of claim 1, wherein said substrate and said conductive traces have a mutual resilience configured to allow said substrate and said conductive traces to stretch and contract in conjunction with one another without breaking the conductive traces.
 6. The sensor of claim 5, wherein said substrate and said conductive traces comprise overlapping stretching parameters providing the mutual resilience.
 7. The sensor of claim 6, wherein said substrate and said conductive traces comprise a mutual resilience to withstand deforming forces that stretch a dimension of the sheet in any direction by an amount between 2 percent and 10 percent.
 8. The sensor of claim 1, wherein said substrate comprises a nonconductive substrate.
 9. The sensor of claim 1, wherein said substrate comprises a single layer of insulating material.
 10. The sensor of claim 9, further comprising respective circuit connections at a first end of at least one of said conductive traces and at an opposite end of said at least one of said conductive traces.
 11. The sensor of claim 1, further comprising a capacitive sensor circuit formed of a second set of said conductive traces on said first side of said flexible substrate.
 12. The sensor of claim 1, further comprising a capacitive shield circuit formed of a third set of said conductive traces on a second side of said substrate.
 13. The sensor of claim 1, further comprising a capacitive sensor circuit formed of a second set of said conductive traces on said first side of said flexible substrate and a capacitive shield circuit formed of a third set of said conductive traces on a second side of said substrate, wherein said resistive circuit, said capacitive circuit, and said capacitive shield circuit each comprise a plurality of layers.
 14. The sensor of claim 13, wherein said resistive circuit comprises a resistive circuit assembly comprising a highly conductive deposit layer of a first conductivity and a moderately conductive deposit layer of a second conductivity that is lower than the first conductivity.
 15. The sensor of claim 13, wherein said capacitive circuit comprises a multiple layer assembly formed alongside but without touching the resistive sensor assembly.
 16. The sensor of claim 15, wherein said capacitive circuit comprises a conductive patterned section and an overlay section.
 17. The sensor of claim 16, wherein said conductive patterned section comprises a highly conductive pattern having a respective conductivity and said overlay section comprises a moderate conductivity that is lower than the respective conductivity of the highly conductive pattern.
 18. The sensor of claim 13, wherein said capacitive shield circuit comprises a highly conductive trace having a respective trace layer of a respectively high conductivity and an overlay layer of a respectively moderate conductivity that is lower than the respectively high conductivity.
 19. The sensor of claim 1, wherein said flexible substrate comprises a non-conductive film.
 20. The sensor of claim 19, wherein said non-conductive film comprises at least one of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide plastics (PI), a thermoplastic polyurethane, and combinations thereof. 